I have a program that runs a thread for each device under test (144) the
program communicates to the Device Under Test (DUT) thru the serial port.  
Originally the program only allowed 1 thread at a time to use the serial port
using CCriticalSection Lock() and Unlock.  I have new hardware that includes
an 8 port serial card that connects thru a mux to a bank of DUT's so once I
select a bank(mux 1 - 18).  I would like to allow all threads of a common
bank of DUT's to run while blocking all other threads.  Last thread of that
bank allows next bank in.  I'm thinking of using the CreateEvent &
WaitForSingleObject as my critical section enablers but am not too familiar
(Yet) with these functions.  I want to make sure that maximum run priority is
given to threads communicating to bank(n).  Any advice will be read and used
for personal gain.  Thanks